Know Your Plant - Harvest

Well organized preharvest and harvest are essential to preserve cannabis quality. Harvest takes place when plants are in peak ripeness. Depending on high you like you should decide the best timing for harvest. Ideally, you want it during the peak window when THC is at its highest levels. The peak window is open 5-7 days, after that point THC starts to degrade. How to harvest at the right moment and get the most out of your plants you can read in next series of posts "Know Your Plant".

Harvest is the first action taken in final stage of growing your plants (we can call it afterlife too)

Harvest -> Trimming -> Drying -> Curing

We can say it's a point in plants life where growth stops and THC cannot increase anymore; it stays the same or decreases. Decreasing can be stopped and THC can be retained by proper handling. Keep in mind that you should avoid prolonged periods of light, temperatures above 27C (80F), friction from hands and dump, humid conditions.
Hanging plants upside down is convenient, simple and effective way to dry your plants. It has nothing to do with "draining THC into the buds".

On most strains flower are mature in 6 – 12 weeks from changing to 12/12 light schedule. On autoflowering strains same happens in 10 – 14 weeks after germination. This is when THC production has peaked but not yet started degradation process (upper mentioned "peak window").
There are two common methods to determine are flowers mature. When at least half of pistils on top of your buds have turned from white to brown, that indicates plants are turning ripe. However, this is not the most accurate way because some of the pistils never go dark and on some plants new, white pistils grow every few weeks.

White pistils – not ready

Brown pistils – ready

Better indicator of peak ripeness are resin glands or trichomes. To see trichomes we need microscope or other magnifying device. Mind that trichomes easy deteriorate if squeezed.
Trichomes turn from crystal clear to milky to amber. Each stage has different potency and effect.

Clear trichomes – still young, not ready

Milky trichomes – at the peak, ready

The best way to gauge your harvest is to combine both methods.

Maturity Stage

Result

Trichomes crystal clear, pistils white

hasn't gained enough potency

Trichome half clear/milky, half of pistils turned dark

buds are still growing, harvested at this stage will give you more energetic high, suitable for sativa dominant strains

Trichomes mostly milky, 2/3 of pistils turned brown

at this stage THC levels are at highest levels, harvested at this point will give the most intense high, cerebral and physical, suitable for sativa/indica strains